Compass.



W. L. MURPHY.

COMPASS. APPLICATION FILED 1320.21, 1909.

Patented May 10, 1910.

UNTTED STATES PATEN T @T FTQE,

WILLIAM LAWRENCE MURPHY, OF DORCHESTER, MASSACHUSETTS.

COMPASS.

To all whom it may concern:

Be it known that I, \VILLIAM LAWRENCE MURPHY, a citizen of the United States, residing at Dorchester, in the county of Suffolk and State of Massachusetts, have invented certain new and useful Improvements in Compasses, of which the following is a specification.

My present invention relates to compasses, my object being to provide a simple and cheap construction which will, however, be strong and eflicient and convenient for carrying in a pocket.

Other objects, and the resultant advantages, of my invention will be apparent from the following description, in which reference is made to the accompanying drawing, in which,

Figure 1 is an elevation showing the prac tical application of my invention. Fig. 2 is a side elevation of the same in the folded position suitable for carrying in a pocket, and, Fig. 3 is a cross-section through the frame, pencil carriage and its adjusting means.

Referring now to these figures, the frame of my compass comprises a pair of longitudinal parallel plates 10 and 11 which are slotted at 12 throughout the major portion of their length and have their extremities 13 offset toward one another in order to bring them into closer proximity. A thumb-ball or handle piece 14 has its shank 15 riveted between the offset extremities at one end of the plates, and rigidly connects the same, while at the opposite end of said plates, the inner circular end of the tapering axis point 16 is riveted though not rigidly, this point being capable of rotatory movement to reverse the same to a position between the plates 10 and 11.

A clamping screw 17 has its threaded shank 18 projecting transversely through the slots 12 of plates 10 and 11, and through an angular portion 19 of the crayon carriage 20 which as shown comprises semi-cylindrical sections 21 ofspringmetal. At its outer end the shank 18 taps into a nut 22 having a transverse tongue 23 entering the slot 12 of the frame plate 11 against the outer surface of which it bears. Thus the pencil carriage is adapted to receive various sizes of pencils, pens or crayons and is movable throughout the length of the slots 12, and when screw 17 is turned to lock the carriage Specification of Letters Patent.

Application filed December 21, 1909.

Patented May 1t), 1911]).

Serial No. 534,298.

in the desired position by compressing the plates 10 and 11 toward one another thus clamping the carriage, the pencil or the like is rigidly clamped at the same time. By this means one adjustment only is necessary to clamp both the carriage and the crayon therein and the reverse being true when screw 17 is released; the adjustment of the carriage and the longitudinal movement of the crayon therein, both for the purpose of increasing or decreasing the sweep of the pencil point, may be easily made.

I claim:

1. A compass comprising juxtaposed frame plates, an axis point projecting from one end of said plates and rotatively connected at its inner end thereto for movement between the same, a carriage between said plates adapted to receive a crayon, and clamping means for said carriage adjustable longitudinally of said plates.

2. A compass comprising juxtaposed frame plates, an axis point at one end thereof, a crayon carriage extending between said plates and comprising a pair of opposing clamping members, and means to compress said frame plates toward one another and upon said carriage and to simultaneously compress said clamping members upon a crayon inserted therebetwe'en, said means beirig adjustable longitudinally of said frame p ates.

3. A compass comprising a pair of juxtaposed frame plates, having opposing longitudinal slots and inwardly offset ends, a handle rigidly connecting one of the ends, an axis point having its inner ends rotatively connected between the opposite ends of said plates, a clamping screw upon one side of said plates having a threaded shank extending through said slots, a non-rotatable nut upon the opposite side of said plates into which said shank engages, and a crayon carriage between said frame plates comprising a pair of opposing crayon clamping members each having an angular portion through which said shank of said clamping screw passes.

In testimony whereof I afiix my signature in presence of two witnesses.

WILLIAM LAWRENCE MURPHY.

Witnesses ELMER O. RICHARDSON, LOUISE C. ARENTZEN. 

